Turbo position 100% on lexia 2.0hdi rhk

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Joined: 04 Nov 2023, 16:59

Turbo position 100% on lexia 2.0hdi rhk

Post by FantasticComa »

Hello everybody, nice to meet you all. Ive been reading here for a few years, finally got to the stage where i need to ask this fantastic bunch a question or two of my own.
Ive been hunting down the cause of this for a while. In no particular order ive
-removed and cleaned turbo vnt
-replaced vnt solenoid to no avail. The two wires to the solenoid one reads constant 12v and the other has a variable voltage it seems.
-Have replaced all vac lines with silicon vac lines, used a pump to suck in the actuator and left it for a few minutes and its all good.

On lexia map and maf values dont follow the expected values when revving, map reads atmospheric always, maf value stays between 480 and 520, but with the position always being 100% i reason they wouldnt read the expected values.
I have a spare map sensor from trying to solve another issue in the past, no change with it connected (has been in storage for a year ish). There is no position sensor on the vnt actuator. No dpf on this model either. Im wondering if the vnt solenoid is supposed to be a switched ground on wire 2? Or if it is a signal wire and that forms part of the ecus turbo position data along with map? Or if the new solenoid has just been duff all along. I would add there is a p0234 code when driving unless your very very careful, and although when driving or stationary the turbo position is always 100%, on the fault code data it says the position was 24% so it suggests it is capable of working, but it also says the air temp was -48 at the time of the fault but the air temp is reading fine on live data so a potential red herring.
Sorry for the essay, trying to avoid throwing a round of new sensors at it haha.
I guess my main question is what happens on wire 2 for the vnt solenoid? And what actually reads turbo position? Anything jump out?
Cheers to anyone willing to read all of this.